Enable nullable for classes under Rename folder (#62453)

* Enable nullable

* Clean up

* Enable other nullable

* Revert "Enable nullable"

This reverts commit 0cebdff.

* Use IsSuccessful flag to handle different cases

src/EditorFeatures/Core/InlineRename/AbstractEditorInlineRenameService.InlineRenameLocationSet.cs

@@ -42,8 +42,6 @@ public async Task<IInlineRenameReplacementInfo> GetReplacementsAsync(string repl
                 var conflicts = await _renameLocationSet.ResolveConflictsAsync(
                     _renameInfo.GetFinalSymbolName(replacementText), nonConflictSymbols: null, cancellationToken: cancellationToken).ConfigureAwait(false);
 
-                Contract.ThrowIfTrue(conflicts.ErrorMessage != null);
-
                 return new InlineRenameReplacementInfo(conflicts);
             }
         }

src/EditorFeatures/Core/InlineRename/AbstractEditorInlineRenameService.InlineRenameReplacementInfo.cs

@@ -16,13 +16,16 @@ private class InlineRenameReplacementInfo : IInlineRenameReplacementInfo
             private readonly ConflictResolution _conflicts;
 
             public InlineRenameReplacementInfo(ConflictResolution conflicts)
-                => _conflicts = conflicts;
+            {
+                Contract.ThrowIfFalse(conflicts.IsSuccessful);
+                _conflicts = conflicts;
+            }
 
             public IEnumerable<DocumentId> DocumentIds => _conflicts.DocumentIds;
 
-            public Solution NewSolution => _conflicts.NewSolution;
+            public Solution NewSolution => _conflicts.NewSolution!;
 
-            public bool ReplacementTextValid => _conflicts.ReplacementTextValid;
+            public bool ReplacementTextValid => _conflicts.ReplacementTextValid!.Value;
 
             public IEnumerable<InlineRenameReplacement> GetReplacements(DocumentId documentId)
             {

src/EditorFeatures/Core/InlineRename/AbstractEditorInlineRenameService.cs

@@ -55,7 +55,7 @@ public async Task<IInlineRenameInfo> GetRenameInfoAsync(Document document, int p
                 return new FailureInlineRenameInfo(EditorFeaturesResources.You_must_rename_an_identifier);
 
             var semanticModel = await document.GetRequiredSemanticModelAsync(cancellationToken).ConfigureAwait(false);
-            var semanticFacts = document.GetLanguageService<ISemanticFactsService>();
+            var semanticFacts = document.GetRequiredLanguageService<ISemanticFactsService>();
 
             var tokenRenameInfo = RenameUtilities.GetTokenRenameInfo(semanticFacts, semanticModel, triggerToken, cancellationToken);
 

src/EditorFeatures/Test2/Rename/RenameEngineResult.vb

@@ -89,6 +89,7 @@ Namespace Microsoft.CodeAnalysis.Editor.UnitTests.Rename
                 Dim result = GetConflictResolution(renameTo, workspace.CurrentSolution, symbol, renameOptions, host)
 
                 If expectFailure Then
+                    Assert.False(result.IsSuccessful)
                     Assert.NotNull(result.ErrorMessage)
                     Return engineResult
                 Else

src/Features/Core/Portable/EncapsulateField/AbstractEncapsulateFieldService.cs

@@ -316,7 +316,7 @@ private async Task<Solution> EncapsulateFieldsInCurrentProcessAsync(Document doc
             var resolution = await initialLocations.Filter(filter).ResolveConflictsAsync(
                 finalName, nonConflictSymbols: null, cancellationToken).ConfigureAwait(false);
 
-            Contract.ThrowIfTrue(resolution.ErrorMessage != null);
+            Contract.ThrowIfFalse(resolution.IsSuccessful);
 
             return resolution.NewSolution;
         }

src/Features/Core/Portable/UseAutoProperty/AbstractUseAutoPropertyCodeFixProvider.cs

@@ -140,7 +140,7 @@ private async Task<Solution> ProcessResultAsync(CodeFixContext context, Diagnost
                 nonConflictSymbols: ImmutableHashSet.Create<ISymbol>(propertySymbol),
                 cancellationToken).ConfigureAwait(false);
 
-            Contract.ThrowIfTrue(resolution.ErrorMessage != null);
+            Contract.ThrowIfFalse(resolution.IsSuccessful);
 
             solution = resolution.NewSolution;
 

src/Tools/ExternalAccess/OmniSharp/Rename/OmniSharpRenamer.cs

@@ -14,7 +14,7 @@ namespace Microsoft.CodeAnalysis.ExternalAccess.OmniSharp
 {
     internal static class OmniSharpRenamer
     {
-        public readonly record struct RenameResult(Solution Solution, string? ErrorMessage);
+        public readonly record struct RenameResult(Solution? Solution, string? ErrorMessage);
 
         public static async Task<RenameResult> RenameSymbolAsync(
             Solution solution,

src/Workspaces/Core/Portable/Rename/ConflictEngine/ComplexifiedSpan.cs

@@ -2,8 +2,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-#nullable disable
-
 using System.Collections.Immutable;
 using System.Runtime.Serialization;
 using Microsoft.CodeAnalysis.Text;

src/Workspaces/Core/Portable/Rename/ConflictEngine/ConflictResolver.Session.cs

@@ -238,7 +238,7 @@ public async Task<MutableConflictResolution> ResolveConflictsAsync()
                     {
                         var definitionLocations = _renameLocationSet.Symbol.Locations;
                         var definitionDocuments = definitionLocations
-                            .Select(l => conflictResolution.OldSolution.GetDocument(l.SourceTree))
+                            .Select(l => conflictResolution.OldSolution.GetRequiredDocument(l.SourceTree))
                             .Distinct();
 
                         if (definitionDocuments.Count() == 1 && _replacementTextValid)

src/Workspaces/Core/Portable/Rename/ConflictEngine/ConflictResolver.cs

@@ -77,27 +77,28 @@ internal static partial class ConflictResolver
             ImmutableHashSet<ISymbol>? nonConflictSymbols,
             CancellationToken cancellationToken)
         {
+            // when someone e.g. renames a symbol from metadata through the API (IDE blocks this), we need to return
+            var renameSymbolDeclarationLocation = renameLocationSet.Symbol.Locations.Where(loc => loc.IsInSource).FirstOrDefault();
+            if (renameSymbolDeclarationLocation == null)
+            {
+                // Symbol "{0}" is not from source.
+                return new ConflictResolution(string.Format(WorkspacesResources.Symbol_0_is_not_from_source, renameLocationSet.Symbol.Name));
+            }
+
             var resolution = await ResolveMutableConflictsAsync(
-                renameLocationSet, replacementText, nonConflictSymbols, cancellationToken).ConfigureAwait(false);
+                renameLocationSet, renameSymbolDeclarationLocation, replacementText, nonConflictSymbols, cancellationToken).ConfigureAwait(false);
+
             return resolution.ToConflictResolution();
         }
 
         private static Task<MutableConflictResolution> ResolveMutableConflictsAsync(
             RenameLocations renameLocationSet,
+            Location renameSymbolDeclarationLocation,
             string replacementText,
             ImmutableHashSet<ISymbol>? nonConflictSymbols,
             CancellationToken cancellationToken)
         {
             cancellationToken.ThrowIfCancellationRequested();
-
-            // when someone e.g. renames a symbol from metadata through the API (IDE blocks this), we need to return
-            var renameSymbolDeclarationLocation = renameLocationSet.Symbol.Locations.Where(loc => loc.IsInSource).FirstOrDefault();
-            if (renameSymbolDeclarationLocation == null)
-            {
-                // Symbol "{0}" is not from source.
-                return Task.FromResult(new MutableConflictResolution(string.Format(WorkspacesResources.Symbol_0_is_not_from_source, renameLocationSet.Symbol.Name)));
-            }
-
             var session = new Session(
                 renameLocationSet, renameSymbolDeclarationLocation,
                 replacementText, nonConflictSymbols, cancellationToken);

src/Workspaces/Core/Portable/Rename/ConflictEngine/ConflictingIdentifierTracker.cs

@@ -2,8 +2,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-#nullable disable
-
 using System.Collections.Generic;
 
 namespace Microsoft.CodeAnalysis.Rename.ConflictEngine

src/Workspaces/Core/Portable/Rename/ConflictEngine/DeclarationConflictHelpers.cs

@@ -2,8 +2,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using System.Collections.Immutable;
@@ -22,7 +20,7 @@ public static ImmutableArray<Location> GetMembersWithConflictingSignatures(IMeth
                                             .Where(m => !m.Equals(renamedMethod) && m.Arity == renamedMethod.Arity);
 
             return GetConflictLocations(renamedMethod, potentiallyConflictingMethods, isMethod: true,
-                (method) => GetAllSignatures((method as IMethodSymbol).Parameters, trimOptionalParameters));
+                method => GetAllSignatures(((IMethodSymbol)method).Parameters, trimOptionalParameters));
         }
 
         public static ImmutableArray<Location> GetMembersWithConflictingSignatures(IPropertySymbol renamedProperty, bool trimOptionalParameters)
@@ -33,7 +31,7 @@ public static ImmutableArray<Location> GetMembersWithConflictingSignatures(IProp
                                             .Where(m => !m.Equals(renamedProperty) && m.Parameters.Length == renamedProperty.Parameters.Length);
 
             return GetConflictLocations(renamedProperty, potentiallyConflictingProperties, isMethod: false,
-                (property) => GetAllSignatures((property as IPropertySymbol).Parameters, trimOptionalParameters));
+                property => GetAllSignatures(((IPropertySymbol)property).Parameters, trimOptionalParameters));
         }
 
         private static ImmutableArray<Location> GetConflictLocations(ISymbol renamedMember,
@@ -57,10 +55,8 @@ public static ImmutableArray<Location> GetMembersWithConflictingSignatures(IProp
             {
                 if (signatureToConflictingMember.TryGetValue(signature, out var conflictingSymbol))
                 {
-                    if (isMethod)
+                    if (isMethod && conflictingSymbol is IMethodSymbol conflictingMethod && renamedMember is IMethodSymbol renamedMethod)
                     {
-                        var conflictingMethod = conflictingSymbol as IMethodSymbol;
-                        var renamedMethod = renamedMember as IMethodSymbol;
                         if (!(conflictingMethod.PartialDefinitionPart != null && Equals(conflictingMethod.PartialDefinitionPart, renamedMethod)) &&
                             !(conflictingMethod.PartialImplementationPart != null && Equals(conflictingMethod.PartialImplementationPart, renamedMethod)))
                         {

src/Workspaces/Core/Portable/Rename/ConflictEngine/MutableConflictResolution.cs

@@ -2,8 +2,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using System.Collections.Immutable;
@@ -22,8 +20,6 @@ namespace Microsoft.CodeAnalysis.Rename.ConflictEngine
     /// </summary>
     internal sealed class MutableConflictResolution
     {
-        public readonly string ErrorMessage;
-
         // Used to map spans from oldSolution to the newSolution
         private readonly RenamedSpansTracker _renamedSpansTracker;
 
@@ -53,9 +49,6 @@ internal sealed class MutableConflictResolution
 
         private (DocumentId documentId, string newName) _renamedDocument;
 
-        public MutableConflictResolution(string errorMessage)
-            => ErrorMessage = errorMessage;
-
         public MutableConflictResolution(
             Solution oldSolution,
             RenamedSpansTracker renamedSpansTracker,
@@ -89,8 +82,8 @@ internal void UpdateCurrentSolution(Solution solution)
             {
                 if (_renamedSpansTracker.IsDocumentChanged(documentId))
                 {
-                    var document = CurrentSolution.GetDocument(documentId);
-                    var root = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
+                    var document = CurrentSolution.GetRequiredDocument(documentId);
+                    var root = await document.GetRequiredSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
 
                     // For the computeReplacementToken and computeReplacementNode functions, use 
                     // the "updated" node to maintain any annotation removals from descendants.
@@ -161,9 +154,6 @@ internal void AddOrReplaceRelatedLocation(RelatedLocation location)
 
         public ConflictResolution ToConflictResolution()
         {
-            if (ErrorMessage != null)
-                return new ConflictResolution(ErrorMessage);
-
             var documentIds = _renamedSpansTracker.DocumentIds.Concat(
                 this.RelatedLocations.Select(l => l.DocumentId)).Distinct().ToImmutableArray();
 

src/Workspaces/Core/Portable/Rename/ConflictEngine/RelatedLocation.cs

@@ -2,8 +2,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using System.Runtime.Serialization;
@@ -52,7 +50,7 @@ public RelatedLocation(TextSpan conflictCheckSpan, DocumentId documentId, Relate
         public RelatedLocation WithType(RelatedLocationType type)
             => new(ConflictCheckSpan, DocumentId, type, IsReference, ComplexifiedTargetSpan);
 
-        public override bool Equals(object obj)
+        public override bool Equals(object? obj)
             => obj is RelatedLocation location && Equals(location);
 
         public bool Equals(RelatedLocation other)

src/Workspaces/Core/Portable/Rename/ConflictEngine/RelatedLocationType.cs

@@ -2,8 +2,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-#nullable disable
-
 using System;
 
 namespace Microsoft.CodeAnalysis.Rename.ConflictEngine

src/Workspaces/Core/Portable/Rename/ConflictEngine/RenamedSpansTracker.cs

@@ -2,8 +2,6 @@
 // The .NET Foundation licenses this file to you under the MIT license.
 // See the LICENSE file in the project root for more information.
 
-#nullable disable
-
 using System;
 using System.Collections.Generic;
 using System.Collections.Immutable;
@@ -12,6 +10,7 @@
 using System.Threading.Tasks;
 using Microsoft.CodeAnalysis.CodeCleanup;
 using Microsoft.CodeAnalysis.Formatting;
+using Microsoft.CodeAnalysis.Shared.Extensions;
 using Microsoft.CodeAnalysis.Simplification;
 using Microsoft.CodeAnalysis.Text;
 using Roslyn.Utilities;
@@ -48,7 +47,7 @@ internal void AddComplexifiedSpan(DocumentId documentId, TextSpan oldSpan, TextS
                 _documentToComplexifiedSpansMap[documentId] = spans;
             }
 
-            spans.Add(new MutableComplexifiedSpan() { OriginalSpan = oldSpan, NewSpan = newSpan, ModifiedSubSpans = modifiedSubSpans });
+            spans.Add(new MutableComplexifiedSpan(originalSpan: oldSpan, newSpan: newSpan, modifiedSubSpans: modifiedSubSpans));
         }
 
         // Given a position in the old solution, we get back the new adjusted position 
@@ -124,6 +123,14 @@ private class MutableComplexifiedSpan
             public TextSpan OriginalSpan;
             public TextSpan NewSpan;
             public List<(TextSpan oldSpan, TextSpan newSpan)> ModifiedSubSpans;
+
+            public MutableComplexifiedSpan(
+                TextSpan originalSpan, TextSpan newSpan, List<(TextSpan oldSpan, TextSpan newSpan)> modifiedSubSpans)
+            {
+                OriginalSpan = originalSpan;
+                NewSpan = newSpan;
+                ModifiedSubSpans = modifiedSubSpans;
+            }
         }
 
         internal void ClearDocuments(IEnumerable<DocumentId> conflictLocationDocumentIds)
@@ -149,7 +156,7 @@ internal async Task<Solution> SimplifyAsync(Solution solution, IEnumerable<Docum
             {
                 if (this.IsDocumentChanged(documentId))
                 {
-                    var document = solution.GetDocument(documentId);
+                    var document = solution.GetRequiredDocument(documentId);
 
                     if (replacementTextValid)
                     {
@@ -171,11 +178,11 @@ internal async Task<Solution> SimplifyAsync(Solution solution, IEnumerable<Docum
                         complexifiedSpans.Clear();
                     }
 
-                    var root = await document.GetSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
+                    var root = await document.GetRequiredSyntaxRootAsync(cancellationToken).ConfigureAwait(false);
 
                     // First, get all the complexified statements
                     var nodeAnnotations = renameAnnotations.GetAnnotatedNodesAndTokens<RenameNodeSimplificationAnnotation>(root)
-                        .Select(x => Tuple.Create(renameAnnotations.GetAnnotations<RenameNodeSimplificationAnnotation>(x).First(), (SyntaxNode)x));
+                        .Select(x => Tuple.Create(renameAnnotations.GetAnnotations<RenameNodeSimplificationAnnotation>(x).First(), (SyntaxNode)x!));
 
                     var modifiedTokensInComplexifiedStatements = new HashSet<SyntaxToken>();
                     foreach (var annotationAndNode in nodeAnnotations)